Glass tank construction



Aug. 17 ,1926.

GLASS TANK CONS TRUCTION K.G.KUTCHKA Filed Dec. 10, 1925 2 Sheets*Sheet2 lNVENTOR Patented Aug. 17, 1926.

UNITED STATES 1,596,666 PATE-NT OFFICE.

KARL G. KUTCHKA, OF WILKINSBURG, PENNSYLVANIA; ASSIGNOR T PITTSBURGHPLATE GLASS COMPANY, A CORPORATION OF PENNSYLVANIA.

Grass TANK coN.`sTnUcT1oN.

Application led December 10, 1925. Serial No. 74,556.

The invention relates to a glass tank construction, and vmoreparticularly to the forehearth or drawing tank, as .used in themanufacture of window glass, although the inven- 5 tion is not limitedto use in such construction. The invention is illustratedas applied tothe lid or closure of the drawing opening, but is applicable to the top:wall or arch of any glass tank or furnace, where it 1s desired to heatthe glass rapidly from above. In the manufacture of glass from a tank bythe cylinder process, it is necessary to remelt or recondition the glassin the forehearth after each cylinder is drawn, in order to put theglass bath in condition for the next draw.

Similarly, in the drawing of a sheet continuously from the bath, itbecomes necessary after several'hours to discontinue the draw, coverthe? drawing opening, and bring the temperature of the body of glass upa substantial amount before starting another draw. The embodiment of theinvention here illustrated and described, is designed to facilitate thisreheating operation, and reduce the time required to a minimum. Brieflystated, this construction involves a heating arrangement for the coveror lid of the drawing opening, to which heating ,means are applied, sothat a great degree of heat may be directed upon the surface of the bathfrom which the draw has just been made, and which comprises that portionof glass inthe furnace havin the lowest temperature. This is prefera 1yaccomplished by the inducin of surface combustion on the lower face of te lid, bringing it to a white heat in opposition to the glass to bereduced immediately beneath; but it will be understood that theinvention is not limited to use 4o of surface combustion, either in partor in whole, although this is preferred, because ofthe greatertemperature available and because of the greater economy involved. One

- embodiment of the invention is illustrated in y the accompanyindrawings wherein:

Figure 1 is a p an view of a drawing tank with the improvement a pliedthereto. Fig. 2 is a vertical section t rough the drawing tank 4on'theline II-II of Fig. 1. Fig. 3`

is a vertical section through the tank on the line III-III of Fig. 2,with one half of the cover or top shown in side elevation. And Fig. 4 isan enlarged section .through the cover member or late.

Referring to t e drawings, 1 is a forehearth or drawing tank havingcommunication at its right hand end (Fig. 2) with a melting tank, theend wall 2 only ofwhich is shown. The glass level in the tank isindicated by the line 3, and beneath this level is preferably located` arefractory bar 4a to act as a guide for the sheet which is drawn from apoint above the bar by'suitable drawing means, not shown lspaced abovethe surface of the glass is the top of the tank, including the`L-shapedrefractory members 4 and 5 and the refractory members 6, .7, 8,9 and 10. The space between the horizontal flanges of the L-shapedmembers 4 and 5 constitutes the drawing opening, such drawing opening.being illustrated as closed for the remeltino` operation by the covermembers 11,11. nEach cover member consists of a refractory plate 12,preferably clay reenforced, and supported by the metal side members 13and 14, to which are secured the metal plates 15 and 16 adapted' to reston the horizontal flanges of the members 4 and 5. Two cover membersll,11 are employed instead of a single member to facilitate handling as theweight of these parts is very consi erable.

Bolted to .the tops of the reenforcing members 13 and 14 are themanifolds 17 17 eachhaving an elbow 18 at its end, to which isdetachably secured a connection 19 including a iiexible pipe 20 Theflexible pipes are e supplied with a combustible mixture under pressureby the connection 21-supp1ied b a suitable fan 22. Each manifold 1sprovided with a rib 23 which is perforated, as indicated at 24, for theinsertion of a hook, by means of which the cover sections may be movedinto and out of positionfrom an over-j head crane, not show -j 3195 Therefractory plate 12 is provided with z a pluralit. of vertical passages25 of small diameter eading from the space 26 inside the manifold 17(Fig. `4) down to a point adjacent the lower face of the plate wherethey terminate in enlargements 27 which serve as combustion recesses. Inoperation, the bustible mixtureof gas and air is supp 'ed through thepassages 25 under relat'rv `y high pressure and combustion occurs in therec 27 and overl the lower face of the .plate 12. The flow of the gasand air, and this mixture in burning ermeates the surface of the claysurrounlng the recesses 27 and also the surface constituting thelower'face of the plate 12, so that an intense surface combustionoccurs, bringing the lower side of the plate and the interiors of therecesses to an incandescent heat. Under these conditions of surfacecombustion, a much higher temperature is secured than would otherwise bepossible with ordinary Bunsen burners and the economy of fuelis verysubstantially increased. This intense heat applied immediately` abovethe surface of the glass from which the drawing has occurred, veryquickly reduces the glass .to the same condition as the body of glass inthe tank 1, so that in a very short time, the glass is in condition lforanother draw and the cover members may be removed and a new drawinstituted. A

In order to prevent a leakage of gas and air between the lower faces ofthe manifold members 17 and the upper faces of the clay plates 12, therefractory packing 28 o f asbestos or other suitable lmaterial isemployed, which packing also servesthe additional function of insulatingthe upper face of the clay plate 12 from the 4surface of the manifold,so that the injury to the manifold due to the high temperature of theclay is avoided.

What I claim is:

1. The combination :with a glass tank, of a refractory top member in oposition to the surface of the glass provlded with a plurality ofpassages leading downward through said member, and means for supplying akmixture of gas and air through said passages.

2. The combination with a glass tank, of a refractory top member in oosition to the surface of the glass provi ed with a plurality ofpassages leading downward through said member, and having downwardlyopening enlargements at their lower ends, and means for supplying amixture of gas andair through said passages.

3. The combination with a glass drawing tank having a refractory roof orclosure above the glass withv a drawing opening therethrough, of aremovable cover plate supplying a mixture of gas and air through saidpassages.

4. The combination with a glass drawing tank having arefractory roof orclosure above the glass with a drawing opening therethrough, of aremovable cover plate of refractory material for said opening providedwith a plurality of passages leading downward therethrough, and havingdownwardl opening enlargements at their lower en s, and means forsupplying a mixture of gas and air through said passages.

5. The combination with a glass tank, of a refractory top member inopposition to the surface of the glass, and having its lower facerecessed so as to promote sur face' combustion, and means for supplyinga mixture of gas and air to such recesse face, so as to secure surfacecombustion over the surface thereof.

6. The combination with a glass drawing tank having a refractory roof orclosure above the glass with a drawing opening therethrough, of aremovable cover late of refractory material for said opening aving itslower face recessed so as to promote surface combustion, and means forsupplying.a mixture of gas and air to said recessed face, so as tosecure surface combustion over the surface thereof.

7. The combination with a glass tank, of a refractory top member inopposition to the surface of the glass, and having its lower facerecessed so as to promote surface combustion,and means for supplying amixture of gas and air through said member to such recessed face, so asto secure surface combustion over the surface thereof.

In testimony whereof, I have hereunto subscribed my name this 5th day ofDecember, 1925.

KARL G. KUTCHKA.

